try box.co.uk they seem to have some decent prices. Maybe wait for cyber monday as well the prices might drop
Any semi decent laptop is around £500 at 15.6" there doesn't seem to be much in the way of budget laptops at the moment without going 2nd hand.
If they want new PC specialists have this
https://www.pcspecialist.co.uk/noteb...raNoteVI-S-15/
It doesn't seem to bad for the price. I've used these a number of times laptops have been fine. There doesn't seem to be much around on the cheap new market that's worth less than £400 new